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EVAL-IMM101T
Smart IPM evaluation board application note
Thermal Characterization
6
Thermal Characterization
Figure 14, Figure 15, Figure 16, Figure 17, Figure 18, Figure 19 show the thermal characterizations of the three
part numbers. The tests reported in Figure 14, Figure 15, Figure 16 have been performed under the following
conditions: t
amb
=25°C, different phase current values until the case reaches 105°C, two PWM frequencies (6 and
16kHz) and two different modulation types (3-phase modulation and 2-phase flat bottom modulation). The tests
reported in Figure 17, Figure 18, Figure 19 have been performed under the following conditions: t
amb
=60°C,
different phase current values until the case reaches 105°C, two PWM frequencies (6 and 16kHz) and two different
modulation type (3-phase modulation and 2-phase flat bottom modulation). 2-ph flat bottom modulation allows
the reduction of the switching losses compared with 3-phase SVPWM (symmetrical placement of zero vectors).
For the test with t
amb
=60°C, the 3-phase modulation has not been used. For all the tests, the phase current has
been limited to 600 mArms in order to avoid damage to the motor used for the tests. A FR4 PCB with 2oz copper
has been used and the PCB layout is shown in Figure 20.
Figure 14
IMM101T-015M Thermal Characterization, t
amb
=25°C, different phase current values until the
case reaches 105°C, FR4 PCB with 2oz copper
0
20
40
60
80
100
120
180,0
230,0
280,0
330,0
380,0
t
ca
se
[°
C]
Phase Current [mA
rms
]
IMM101T-015M, Thermal Characterization t
amb
=25°C
3-phase modulation 16kHz
2-phase modulation 16kHz
3-phase modulation 6kHz
2-phase modulation 6kHz
